This invention lies in the field of electrically powered motor vehicles and is directed to such vehicles which are strong and light structurally, and which minimize electrical problems while retaining many features found in conventional vehicles having internal combustion engines, so that the transition from driving a conventional vehicle to the electric type will not involve confusion or difficulty.
Electric vehicles have been in use since the turn of the century and have taken many forms. The early passenger vehicles were very heavy and slow and had very short range. They were adequate for many years because their users desired to proceed slowly in any event, and traveled only short distances to shop or visit friends. The batteries could be charged overnight so that the short range on a full charge caused no inconvenience.
Commercial vehicles were developed which were big enough and strong enough to carry a larger supply of batteries which gave them considerably more range, although it was still short. These vehicles were highly suitable for use on routes calling for delivery of foods such as bread and milk. Such routes called for many stops, but the total distance traveled in a day was within the range that was available. Various vehicles of this type are in continuing use today.
More recently, golf carts have come into constantly increasing use, not only for use in playing the game but also for shopping or the like, as in the case of the early passenger vehicles. They are quite satisfactory for such purposes but they are not suitable for general use. They have low speed and short range, and most are not adequately equipped to protect the occupants against inclement weather. They are not rugged enough to cope with traffic, and their low speed is a hazard to other vehicles.
Many experimental vehicles have been produced in recent years in an effort to produce a machine which has the general appearance of a conventional automobile, is large enough and rugged enough to travel in traffic, has enough speed to keep up with traffic, and yet has enough range to be suitable for general urban use. Such a vehicle must have a top speed of more than 50 miles per hour and a range of over 75 miles.
The total amount of power and energy available depends on the capacity of the best batteries currently available. The speed and range in turn are also limited. Consequently, the approach has been to provide space for as many batteries as possible and to provide a vehicle which is as light as possible, while providing the battery space and a rugged construction for safety in use.